Listen to Robert Emmerich introduce The Big Apple, a hit song from 1937. Music written by Bob and performed by Tommy Dorsey's Clambake Seven with Bob on piano. Lyrics written by Buddy Bernier and sung by Edythe Wright. Audio provided by Dorothy Emmerich.

American humorist Robert Benchley (1889-1945) was written about in the syndicated newspaper column “In Hollywood” by Paul Harrison in September 1937:

“Hollywood. Sept. 9.—Short takes Robert Benchley had spent a long, wilting day under the hot lights on the ‘Live, Love and Learn’ set. He sighed, ‘Golly, it’ll be nice to get out of this wet suit and into a dry Martini!’”

The actor Charles Butterworth (1896-1946) said “You oughta get out of those wet clothes and into a dry martini” in the movie Every Day’s a Holiday (1937). Benchley used the line in the movie The Major and the Minor (1942).

Benchley is usually associated with the line, although he stated in 1942 that he’d read it in a joke book.

Wikipedia: Robert BenchleyRobert Charles Benchley (September 15, 1889 – November 21, 1945) was an American humorist best known for his work as a newspaper columnist and film actor. From his beginnings at the Harvard Lampoon while attending Harvard University, through his many years writing essays and articles for Vanity Fair and The New Yorker and his acclaimed short films, Benchley’s style of humor brought him respect and success during his life, from New York City and his peers at the Algonquin Round Table to contemporaries in the burgeoning film industry.

Wikipedia: Charles Butterworth (actor)Charles Edward Butterworth (July 26, 1896 – June 13, 1946) was an American actor specializing in comedy roles, often in musicals.
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He is credited with the quip “Why don’t you slip out of those wet clothes and into a dry martini?” from Every Day’s a Holiday.

10 September 1937, The Daily News (Frederick, MD), “In Hollywood” by Paul Harrison (NEA Service Staff Correspondent), pg. 13, col. 3:
Hollywood. Sept. 9.—Short takes Robert Benchley had spent a long, wilting day under the hot lights on the “Live, Love and Learn” set. He sighed, “Golly, it’ll be nice to get out of this wet suit and into a dry Martini!”

7 June 1942, The Sun (Baltimore, MD),"Dry Martini Gag Hounds Benchley Down The Years” by Amy Porter, sec. 1, pg. 4:
New York.
It was a good joke when it was new. It’s still a pretty good joke, but RObert Benchley would rather not have any more truck with it.

“It never belonged to me in the first place,” said Benchley.

“I saw it in a joke book one day—this was out in Hollywood—and when I went to the studio I said to a fellow, “Say, here’s a pretty good one I found in a book, guy comes home in the rain and says “I’ll have to get out of these wet clothes and into a dry martini.’”

He Gets The Credit
“The fellow liked it, and he told it around here and there and that night somebody saw me and said, ‘Bob, that new line of yours is okay.’

“‘What line?’ I asked him, and he said, ‘you know—I’ll have to get out of these wet clothes and into a dry martini. Yes sir, that’s all right.”

“‘Oh that’s not mine,’ I said. ‘I read it in a book,’ I said. That’s what I said before witnesses.”

A couple of years later, when Bob Benchley had grown to such stature as an actor, author and master of wit that people wanted to know where he was born and did he go to school, which he didn’t any more than he could help, a magazine writer who was piecing together a piece about him asked:

“Can you please give me some good jokes of yours to quote in this piece?”

Regarding the origin of the line “Why don’t you get out of those wet clothes and into a dry martini?”, discussed by Sander Vanocur in “Benchley’s Martini” (letter, July 12), here is what I learned while researching “The Movie Dialogue Quiz Book”:

In “The Major and the Minor,” a 1942 movie, Robert Benchley says to Ginger Rogers, “Why don’t you get out of that wet coat and into a dry martini?” Although Billy Wilder was the movie’s co-writer and director, he said Benchley came up with the line.

Benchley, in his turn, attributed it to his friend Charles Butterworth. Indeed, in the 1937 “Every Day’s a Holiday” (starring and written by Mae West), Butterworth tells Charles Winninger, “You ought to get out of those wet clothes and into a dry martini.”
DIANE GIDDIS
New York, July 14, 1994

OCLC WorldCat recordI must get out of these wet clothes and into a dry martini
Author: Alexander Woollcott; Alan Stein
Publisher: Parry Sound : Church Street Press, 1997.
Edition/Format: Print book : English